A. Field of the Invention
This invention relates generally to machines or devices for embossing alpha-numeric characters on flexible sheets such as plastic or metal credit cards or nameplates and so forth. More particularly, the invention involves an embossing machine comprising two constantly rotating embossing wheels carrying radially movable embossing molds about their peripheries. One embossing wheel carries male embossing molds in which the alpha-numeric character on each mold projects outwardly. The second embossing wheel carries female or intaglio embossing molds on which the matching alpha-numeric character of each mold projects inwardly. A selected character is embossed in a flexible sheet positioned in the bite of the two embossing wheels by moving the two corresponding molds bearing the male and female representations of the selected character outwardly before they revolve through the bite position. Embossing of the flexible sheet is accomplished by a combination rolling and squeezing motion of the two selected molds.
Provision is made, as a part of the invention, for transporting the flexible sheet to be embossed so as to position it to successively receive the next embossed character. The sheet is moved by the machine of this invention along perpendicular axes for this purpose.
An electronic control system is provided, as part of the invention, for continually sensing the instantaneous position of the rotating embossing wheels. When electronic signals are received, indicating the character to be embossed, the control system determines when the selected character molds pass a reference point about the peripheries of the embossing wheels. At that point, the system actuates mold setting solenoids which cause the selected corresponding embossing molds in each wheel to be cammed outwardly along radii of the wheels.
Also as part of the invention, provision is made for a mechanical camming device for moving selected molds outwardly and locking them in an extended position for embossing the selected character in the interposed flexible sheet. After the embossing of each character, the previously selected molds are unlocked and returned to their original inward position.
In the embodiment shown herein, character selection signals are derived by manual operation of an alpha-numeric keyboard in the usual fashion. The invention contemplates, however, that data signals for selection of characters to be embossed may originate from any suitable source, such as magnetic tape, telephone lines, computer memory, video terminals, and so forth.
B. Description of the Prior Art
Many prior art devices have been developed for causing an alpha-numeric character to be embossed on flexible sheets. The art in general is long established, as embossing machines, as will be shown in this section, were designed in large numbers during the prior century.
In the last several years, however, the field has grown tremendously due primarily to the greatly increased use of plastic credit and identification cards. Thousands of companies in the United States and many foreign countries currently issue such cards. Many of the national card companies issue hundreds or even thousands of new or updated cards daily. Obviously, in the face of such increased demand, there is a substantial need for embossing machines capable of producing large numbers of cards accurately, quickly, quietly and cheaply.
It should be understood also that embossing machines, as currently used in many applications, must accept embossing data from sources other than mechanical or electro-mechanical keyboards. As one example, large national companies often initially keypunch card data into standard IBM cards. After verification, the punched data is transferred to magnetic tape for use in card preparation, customer billing, accounting and so forth. The portion of the data to appear in an issued credit card is abstracted and transferred to a further magnetic tape. That tape may then be used to supply embossing data for preparation of the cards.
As a second example, embossed plastic cards are used as part of registration and inquiry systems for conventions attracting large numbers of attendees. In one such system, arriving attendees provide registration information to operators of video terminals. The information is keyed into the terminals by the operators and visually displayed for verification. Following verification, the information is transmitted from the video terminal to a computer for editing and storage. The computer, in turn, in one of its programmed tasks, extracts certain data from the entered information, typically, name, address, and company name, and transmits the extracted data to a card embossing machine. A plastic card is then prepared by the embossing machine for the attendee's use as a name badge and inquiry card to be furnished to exhibitors for recording if the attendee desires to be mailed product information, catalogs and so forth. The entire process of card preparation after the entered date is verified by the video terminal operator requires only a few seconds. Since attendees at large conventions typically arrive at about the same time, the computer controlled embossing machine must produce thousands of embossed cards within a very short period.
Other applications of embossing machines require keyboard input of embossing data and production of relatively fewer cards. For example, many hospitals have adopted a records system in which each entering patient is provided an embossed plastic card bearing, inter alia, the patient's name and account number. All charges of that patient for items such as drugs and other supplies are registered using this card. An embossing machine for card preparation in this type of system must be capable of receiving keyboard input, relatively silent operation, must be compact in size and low in cost.
Other types of sheets and cards, of course, are embossed by devices of the prior art and may be embossed by the machine of this invention. For example, metal name and specification plates for attachment to machinery may be embossed in the same fashion as are the plastic credit cards described above.
Most prior art embossing machines for the production of large numbers of embossed cards, as in the national card company example used above, are extremely complex, very large machines costing many tens of thousands of dollars. They generally operate from an array of punches and dies with the actual embossing performed by a selected punch and die struck by hammers or anvils. Generally, the sheet or card to be embossed is moved by transport apparatus along perpendicular axes between the punch and die arrays to receive each successively embossed character. In at least one machine, the entire punch apparatus is moved along perpendicular axes. As a result, such machines are quite noisy. Due to the very great number of operating parts which are struck or impacted by other parts, such machines also experience relatively short component life. An example of such an embossing machine is found in U.S. Pat. No. 3,223,218 to Terzariol.
Traditionally, the smaller embossing machines capable of operating from a keyboard have often employed principles of operation other than that of the Terzariol design. For example, U.S. Pat. No. 3,785,470 to Schacht discloses an embossing machine wherein the embossing characters are arranged around the periphery of a rotating wheel. When an operator depresses a key on the keyboard, a clutch is engaged which stops the character wheel. The sheet or card to be embossed with the selected character is then raised upwardly against the stationary selected character. As the embossed sheet or card is withdrawn, the clutch is disengaged and the character wheel begins to revolve again. Similar embossing machines may be seen in U.S. Pat. No. 520,238 to Libbey, U.S. Pat. No. 2,213,831 to Bates, and British Pat. No. 9,800 to Barker (1894).
Generally, disadvantages are found in machines such as the foregoing in that they may be operated only by a manual keyboard, the start-stop motion of large masses causes vibration and wearing of machine parts, complex clutching mechanisms are required and, because of the inertia of the large moving parts which are clutched, the machines are relatively slow. Further, as a general rule, they are quite noisey, making them inappropriate for many working environments.
A more widely used principle of modern embossing machine operation is disclosed in U.S. Pat. No. 3,763,986 to Deutsch. In the Deutsch design, sets of male and female embossing characters are arranged around the facing inside rims of a pair of embossing wheels rotating on the same axis. Selection of a character by operation of a manual keyboard causes a clutch to stop the rotating embossing wheels. Anvils, or some similar device, impact the selected characters and cause the character to be embossed at the appropriate location in the sheet or card. After the embossing operation, the clutch is disengaged allowing the wheels to rotate until the next character is selected.
A similar design is shown in U.S. Pat. No. 3,029,920 to Seifried. The Seifried embossing machine includes movable character punches and dies which are driven parallel to the axis of rotation of the embossing wheel when struck by anvils. Like the Deutsch design, the Seifried embossing machine is clutched when a character is embossed.
As previously stated, the start-stop operation of the embossing wheels is noisy, requires complex mechanical clutching and results in wear of components. Further, also as previously stated, the inertia of the clutched embossing wheels restricts the speed of the machine.
Other types of embossing machines have been designed in which male embossing characters are arranged around the periphery of a first embossing wheel and female characters around a second wheel. Typical of devices of this type is the embossing machine described in U.S. Pat. No. 2,250,567 to Bates. The Bates machine is used for embossing small metal bands such as are used for marking legs of poultry. The embossing wheels are geared to rotate together and are positioned manually by the operator to select a character for embossing. When the wheels are in the proper position to emboss the desired character, a foot petal is depressed by the operator, causing the wheels to move together radially. Similar embossing machines may be found disclosed in U.S. Pat. No. 2,221,424 to Rexford, et al., and German Pat. No. 6,677 (1878).
Such devices of the prior art, however, are unacceptable for high-volume production of embossed cards or sheets. First, selection of desired embossing characters is accomplished manually and, therefore, machine operation is quite slow. Secondly, the requirement of radial travel of a relatively large mass of one of the embossing wheels also insures low speed and vibration. Finally, component wear is caused by the change of movement direction of large masses and the necessary absorbtion of energy.
Finally, the male-female character approach has been incorporated in embossing machines wherein the characters are carried by flexible bands. For example, U.S. Pat. No. 3,010,387 to Deutsch discloses such a design in which the characters and the bands are integrally molded from nylon. After the band is positioned above and below the proper location of the plastic card, anvils strike the two bands, forming an embossed character. A somewhat similar design for embossing a plurality of characters simultaneously is disclosed in U.S. Pat. No. 3,666,072 to Austin.
Such devices, while acceptable for use in production of low numbers of embossed sheets or cards, are unsatisfactory for embossing high numbers of cards or embossing metal plates. Also, as with any flexible band repeatedly impacted with a metal anvil or hammer, substantial wear of the band and characters is encountered.